Jose Ferrer
From the moment he appears he steals this movie, particularly in his drunken scene. But even his quiet moments are great. His lawyer portrayal is the most lawyerly I've ever seen. I'd seen this years ago and recalled it as one of Bogart's best performances, and I think it is, but Ferrer really shines.
"I'll book you. I'll book you on something. I'll find something in the book to book you on."